Electric switch



` me. 23, 1923. Y

M. A. PERSSON ELECTRIC SWITCH Fi1eduune`2. 1922 2 sheets-sheet 1 Get. 23, 1923.

M. A. PERSSON ELECTRIC SWITCH Filed 'June' 2. 1922 2 Sheets-Sheet 2 Imm: 7771712' MJ. erssa/ I Patented Oct. 23, 1923.

NiTED STATES MARTIN .AUGUST PERSSON, 0F MALMO, SWEDEN.

ELECTRIC SWITCH.

Application led June 2,

To all 'whom t may concern Be it known that l, MARTIN AUGUST PERS- soN, a citizen of Swedemand residing at Malmo, in the Kingdom of Sweden, have invented a certain new and useful Electric Switch, of which the following is a specification.

My invention relates to an electric switch of a simple and attractive construction which at the same time is reliable and eective in its action. The essential feature of the invention consists of a circular insulating member, on the outside of which two rotatable rings are concentrically arranged one rotatable around the other and connected with each other by means of a spring v carrier device. The insulating member is in the usual manner provided with peripheral shoulders and contact members while the inner ring has spring contact blades coacting with the shoulders and contact members. When the outer ring is being rotated in a certain direction it also rotates the inner ring by means of the carrier device which may vary considerably in form and construction and which chiefly serves the purpose to ensure a momentary breaking of the electric circuit by giving the inner ring a sudden quick movement when the contact blades of the .latter are leaving the contact members of the insulatin member and dropping behind the perlpheral shoulders. In order to improve the sudden interruption of the circuit the circumference of the insulating member has preferably a convex form between two adjacent shoulders. This ensures that the pressure of the contact blades upon the circumference of the insulating member when turning the rings is reduced immediately before the former drop behind the shoulders. By reducing this pressure the resistance of the blades a ainst the movement of the inner ring wil also be reduced which results in the inner ring receiving a sudden quick movement on account of the sprin force of the carrier device being release by the reduced resistance. A specially simple and cheap construction of the improved switch may be arrived at by providing a plate collar on the outside circumference of the inner ring and cutting tongues in said collar 1922. Serial No. 565,300.

. in the aforesaid manner will contain considerably less arts than all switches of a similar kind hit erto known. The parts of the improved switch are easily exchangeable and cannot be damaged by careless handling as they are well protected and not subjected to forces other than those which normally are present when manipulating the switch. If the outer ring is rotated in a wrong `direction no currentk `carrying or other movable parts in the switch will be affected. The improved switch not being provided with the usual projecting handle or knob may be produced in specially pleasing and decorative styles and furthermore the absence of a knob will not induce the switch to be used as a clothesrack which hitherto usually has been the case and whereby the switch soon became damaged and useless. The switch may be' arranged as multi-pole and as change-overswitch and can further be provided with a plug contact in which case suitable plug holes could be arranged in the insulating member.

The invention is more particularly described with reference to the accompanying drawings in which Figs: 1 and 2 show the improved switch arranged as change-over switch in vertical sections at right angles to each other. Fig. 3 shows a side view, Fig. 4 a horizontal section through the same and Fig, 5 is a top plan view. Figs. 6 and 7 show a one-pole switch of the improved type in vertical and horizontal sections respectively. Figs. 8-11 show the improved switch fitted with a plug contact device, in which Figs. 8 and 9 are vertical sections at right angles to each other, Fig. 10 is a horizontal section and Fig. 11 is a top plan view of the same.

The switch consists of a socket 1 preferably integral with the insulating member 2 around which two concentric rings 4, 8 are arranged and held in position by means of a `suitably fixed cover 3. The inner rotatable ring 4c is fitted with contact blades 7 resting upon the circumference of the insulating member 2 which is provided with peripheral shoulders 5 and contact members 6, while the outer rotatable ring 8 is connected with the inner ring by means of a. spring carrier device. This device may consist for instance of suitably arranged spiral or flat springs but preferably it will have the form as shown in the illustration, according to which a plate collar 9 is fixed to the inner ring 4, the plate collar being provided with one or several flaps 10 bent in such a Way as to project through openings of the plate collar in order to engage notches 11 on the inside of the outer ring 8, so that when the latter is turned in the direction shown by the arrow (Figs. 4, and 10) the inner ring is resiliently carried along with the outer ring. If the latter is turned in the opposite direction the flaps 10 will trail over the notches 11. The contact blades 7 referably consist of tongues fixed to the plate collar 9 and bent through openings 12 arranged in the inner ring 4. The insulating member 2 has between the shoulders 5 such a convex form that the pressure of the contact blades 7 upon the circumference of the former is reduced immediately before the blades drop behind the shoulders, for which purpose the diameter of the insulating member is gradually decreasing towards the shoulders 5. For this reason the friction between the contact blades 7 and the contact members 6 will also be decreased and the spring of the carrier 10 having been somewhat pressed together during the turning of the outer ring will on account of the diminished friction suddenly expand and throw the inner ring slightly forward, so that the contact blades 7 when reaching the shoulders 5 will receive a quick forward movement thus ensuring momentary circuit breaking. The contact members 6 are in the usual manner fixed to the insulating member, for instance by means of screws.

The cover 3 is integral with a tap 13 provided with threads in order to be screwed into corresponding threads in the centre of the insulating member 2. Hollow screws 14 pass through the insulating member and serve the purpose partly to act as clamping connecting pieces and partly to hold down the contact members 6. A ring shaped channel 15 is provided on the inside of the cover 3 to allow for a space for the head of the screws 14. Furthermore holes 16 are arranged through the insulating member for the insertion of screws for fixing the switch to a wall. A switch of this improved type ydoes not in any way. disclose any `connecting contacts. fixing screws or the; like and has an all through smooth and attractive surface without projecting parts except the outer ring 8.

Referring to the modified form shown in Figs. 6 and 7 as a one-pole switch the parts used are identical to those shown in Figs. 1-5 with the exception lthat one of the contact members 6 and one of the contact blades 7 have not been mounted. This shows that the improved switch may suit different purposes by using the same form and the same constructional parts but arranged differently.

Another modification is shown in Figs. 8-11 which relates to a switch of the improved type fitted with a plug contact device. In addition to the characteristic parts previously referred special contact bushings 17 are titted'in holes 18, 19 arranged in the insulating member 2, one of said holes 19 serving at the same time as a contact clamping device similar to that shown in Figs. 1-3 and indicated by 14. The cover 3 is in this case held down by means of the contact bushings 17 going through corresponding holes arranged in the cover. A

Having thus described my invention what I claim and desire to secure by Letters Patent is 1. An electric "switch comprising a circular insulating member provided with peripheral shoulders and contact members, an inner ring provided in the usual manner with spring rubbing contacts resting upon the circumference of the insulating member and coacting with the contact members fixed thereto, said inner ring concentrically and rotatably arranged around the insulating member, an outer ring concentrically and rotatably arranged around the inner ring and a resilient carrier device fixedu to the latter and coacting with the outer ring in such a manner that when turning the outer ring in a certain direction the inner ring is carried along with the' same.

2. An electric switch comprising an insulating member with peripheral shoulders and contacts, two rotatable rings concentrically arranged around the insulating member and one around the other, the inner ring provided with the usual rubbing contacts, a spring carrier device acting between the two rings and said insulating member provided with convex shaped parts between the peripheral shoulders in order to` reduce the pressure of the rubbing contacts on the circumference of the insulating member immediately before said rubbing contacts drop behind said shoulders when turning the rings for the purpose of obtaining a sudden quick movement of the inner ringby means of the spring force of the carrier thus released whereby a momentary circuit breaking is ensured.

3. An electric switch comprising an insulating member with peripheral shoulders and contact members, two rotatable rings concentrically arranged around the insulatspring carrier acting between the two' rings,

a plate collar fixed to the outside circumference of the innerY ring, a number of tongues fastened to said plate collar and openings in the inner ring through which said tongues pass and project to such an extent as to form rubbing contact blades rest# ing upon the circumference of the insulating member.

4. 'An electric switch comprising an insulating member with peripheral shoulders and contact members, two rotatable rings concentrically arranged around the insulating member and one around the other, a plate collar fixed to the outside circumference of the inner ring, a number of flaps fastened theretofsaid fla s bent in such a manner as to become resi ient members and a number of notches arranged on the inside circumference of the outer ring, in which notches the free ends of said flaps may engage so that the outer ring when turning in one direction resilently carries along the inner ring and when turning in the opposite direction it is allowed to be freely revolved upon the inner ring.

In testimony whereof, I have signed my name to this specicaton in the presence of two subscribing witnesses.

MARTIN AUGUST PERSSON.

Witnesses:

H.- BRANznLL, G. PmnssoN. 

